Combined tapered mill for descaling and drifting

The utility model relates to an oil field well repair tool, namely, a combined tapered mill for descaling and drifting. The combined tapered mill comprises a pipe body, wherein a joint buckle connected with a pipe column is arranged at the upper end of the pipe body, four or five scraping alloy paving and welding channel slots are axially formed in the surface of the lower part of the pipe body, the channel slots are internally paved and welded with scraping alloy, water slots are arranged between the scraping alloy channel slots and are provided with a plurality of spraying water holes which are communicated with an inner cavity of the pipe body, and the water holes spray downward toward the scraping alloy by an axial direction of 45 degree. Through scientific arrangement of the scraping alloy channel slots and by combining a waterpower jet principle, the water slots are arranged reasonably; by utilizing constant high pressure spray washing and through scraping and slight milling of the scraping alloy, the d